Sheet feeding cylinder

ABSTRACT

A cylinder for feeding sheets of tinplate to a machine for treating at least one of the faces of the sheets by printing, varnishing or coating. A longitudinal cavity extends into the cylinder from the periphery parallel to the axis thereof. A shaft is located in the cavity and mounted for rocking movement about its axis by control means located beyond one end of the cylinder. A stop and a gripper operable by the rocking of the shaft and arranged to cooperate with the leading edge of a sheet for feeding it. The stop and the gripper are secured to an auxiliary shaft parallel to the first shaft and mounted for rocking movement in said cavity in which it is wholly contained, the two shafts being connected to each other for rocking movement by a transmission linkage comprising a first lever secured to the first shaft and a second lever shorter than the first secured to the auxiliary shaft and a connecting rod pivotally connected to the levers.

United States Patent 91 Bru [ 51 Jan. 29, 1974 1 SHEET FEEDING CYLINDER Michel Bru, Chatenay-Malabry, France [22] Filed: Mar. 20, 1972 [21] Appl. No.: 236,275

[75] Inventor:

[30] Foreign Application Priority Data Mar. 29, 1971 France 7110876 [52] US. Cl. 271/53, 101/409 [51] Int. Cl B65h 5/12 [58] Field of Search. 271/53, 82, 51; 101/409, 410, 101/411 [56] References Cited UNITED STATES PATENTS 3,497,208 2/1970 Reinartz et a1. 271/82 2,699,941 l/1955 Huck et a1. 271/53 1,340,722 5/1920 Leonard 271/53 3,536,321 10/1970 Straube 271/53 2,892,630 6/1959 Schunemann 271/82 X Primary Examiner-Evon C. Blunk Assistant Examiner-Bruce H. Stoner, Jr. Attorney, Agent, or Firm-Diller, Brown, Ramik &

Wight ABSTRACT A cylinder for feeding sheets of tinplate to a machine for treating at least one of the faces of the sheets by printing, varnishing or coating. A longitudinal cavity extends into the cylinder from the periphery parallel to the axis thereof. A shaft is located in the cavity and mounted for rocking movement about its axis by control means located beyond one end of the cylinder. A stop and a gripper operable by the rocking of the shaft and arranged to cooperate with the leading edge of a sheet for feeding it. The stop and the gripper are secured to an auxiliary shaft parallel to the first shaft and mounted for rocking movement in said cavity in which it is wholly contained, the two shafts being connected to each other for rocking movement by a transmission linkage comprising a first lever secured to the first shaft and a second lever shorter than the first secured to the auxiliary shaft and a connecting rod pivotally connected to the levers.

10 Claims, 6 Drawing Figures SHEET FEEDING CYLINDER BACKGROUND OF THE INVENTION This invention relates to a cylinder for feeding sheets, for example sheets of tinplate, to a machine for treating at least one of the faces of the sheets, for example by printing, varnishing, or coating.

In machines of the kind above mentioned it is usual for a sheet to be pushed longitudinally by push-rods between two cylinders, one of which is a cylinder to effect the desired treatment of the sheet and the other of which is a sheet feeding cylinder.

When the sheet has to be located accurately, it is necessary to position the sheet accordingly in relation to the treating cylinder.

This positioning is usually effected in two directions at right angles to one another, that is to say in a direction parallel to the axis of the cylinder and in a direction parallel to the direction of advance of the sheet. For this purpose the sheet is positioned by lateral guides disposed parallel to its direction of advance and by stops carried on the periphery of the sheet feeding cylinder.

In practice the sheet to be treated is introduced into the machine at a linear speed which is higher than the horizontal component of the speed of the stops. A shock therefore occurs when the leading edge of the sheet comes into contact with the stops, and this shock may cause longitudinal rebounding and/or vibration of the sheet.

In both cases the correct positioning of the sheet against the stops is not achieved as soon as the sheet comes into contact with the stops,,and it is known that the accuracy of the positioning of the sheet in relation to the stops, and therefore in relation to the treating cylinder associated with the sheet feeding cylinder cartying the stops, is governed by the time during which the sheet is stressed by application against the stops by means of the push-rod which effects its advance.

Sheet feeding cylinders known up to the present time generally have, mounted in a longitudinal cavity parallel to their axis, a rocking shaft operated by external control means, and it is this shaft which carries at least one stop intended to co-operate with the leading edge of the sheet to be treated.

In practice the rocking shaft also carries at least one gripper associated with the stop and intended for momentarily covering the leading edge of the sheet at the end of the positioning, in order to prevent it from passing over the stop.

However this may be, since the sheet has to pass linearly between the treating cylinder and the sheet feeding cylinder, the positioning must be completed when the leading edge of the sheet passes through the plane containing the axes of the two cylinders.

Consequently, if it is desired that the time of contact between the sheet and the stops of the sheet feeding cylinder should be relatively long, it is necessary for the stops to be mounted pivotally so that, before making contact with a sheet, they project considerably beyond the periphery of the sheet feeding cylinder and can thus be interposed in the path of the sheet.

It is for this reason that the stops are keyed on a shaft rockably mounted in the sheet feeding cylinder, this shaft thus being adapted to move the stops pivotally under the action of control means which are generally composed of a cam co-operating with a roller carried at the end of a lever keyed on'the shaft.

These control means are necessarily outside the sheet feeding cylinder, so that the rocking shaft which carries the stops must necessarily project longitudinally beyond the cylinder.

Consequently, for constructional reasons, the rocking shaft cannot be situated near the periphery of the cylinder in these circumstances it is not possible to give to the stops carried by the cylinder a sufficiently large pivoting angle to ensure that the time allowed for positioning the sheet against the stops will be relatively long.

In order to give some idea of the circumstances it is found that with known sheet feeding cylinders the angular path thereof between the moment when the sheet comes for the first time into contact with the stops carried by the cylinder, and the moment when the associated gripper or grippers effectively grips or grip this material against the sheet feeding cylinder slightly before the stops on the feed cylinder release the material, is generally at most about 25.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a sheet feeding cylinder which enables the time allowed for positioning a sheet for treatment to be considerably increased.

According to the invention a sheet feeding cylinder comprises a longitudinal cavity which extends into the cylinder from the periphery thereof and which is parallel to the axis of the cylinder, a shaft located in the cavity and mounted for rocking movement about its axis by control means located beyond an end of the cylinder, and at least one stop and at least one gripper operable by rocking of said shaft and arranged to cooperate with the leading edge of a sheet to effect feeding thereof, wherein the stop and gripper are secured to an auxiliary shaft parallel to said first-mentioned shaft and mounted for rocking movement in said cavity and wherein the two shafts are connected to one another for rocking movement thereof by a transmission linkage. The transmission linkage may comprise a first lever secured to said first-mentioned shaft, a second lever secured to the auxiliary shaft, and a connecting rod articulated to the levers.

In a sheet feeding cylinder according to the invention it is the auxiliary shaft which effects the pivoting of the stop or stops of the sheet feeding cylinder.

Since the auxiliary shaft is rocked by the firstmentioned shaft, it may be completely contained longitudinally in the cavity in the feed cylinder, because it does not need rocking drive means outside the latter.

The auxiliary shaft can, therefore, be disposed closer to the periphery of the cylinder than the firstmentioned shaft and considerably forward of the latter considered in the direction of rotation of the sheet feeding cylinder. The lever arm effecting the rocking movement of the stops carried by the auxiliary shaft can be of considerable length in relation to the lever arm as compared with a similar lever arm provided to effect rocking of the stops in known sheet feeding cylinders.

Thus the projection of the stops carried by the sheet feeding cylinder according to the invention, in relation to the periphery of the cylinder, is considerably increased, with the result that the stops can effect the positioning of a sheet during a far longer interval of time as compared with known sheet feeding cylinders.

It has been found that the angular path of a sheet feeding cylinder according to the invention during positioning of a sheet may be up to 45.

In order that the invention may be clearly understood one embodiment thereof will now be described, by way of example, with reference to the accompanying diagrammatic drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a sheet feeding cylinder according to the invention;

FIGS. 2, 3 and 4 are partial cross-sectional views to an enlarged scale, taken respectively on the lines II-II, IlI-III and IV--IV, FIG. 1;

FIG. 5 is a diagrammatic view illustrating the position of the feed cylinder at the moment when a sheet comes into contact with stops carried by the cylinder; and

FIG. 6 is a similar view to FIG. 5 and illustrates the position of the feed cylinder during the gripping of a sheet by grippers associated with the stops carried by the cylinder.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, the sheet feeding cylinder 10 is mounted for rotation between two side plates 11A, 113, FIG. 1, and at each of its ends is provided with pinions 12A, 128 by which it is rotated by gear wheels not shown.

In a manner known per se the sheet feeding cylinder 10 is provided with a cavity 13 which extends longitudinally of the cylinder and completely over a sector of the periphery of the cylinder. A shaft 14, hereinafter referred to as the main shaft, is located in the cavity 13 and is mounted for rotation in bearings 15 secured to the cylinder. The shaft 14 extends beyond an end of the cylinder 10 and carries a lever 16 provided at its end with a roller 17 arranged to co-operate with a cam 18 secured to the frame 11B.

The profile of the cam 18 is so designed as to effect rocking of the shaft 14 about its axis during the rotation of the cylinder 10.

The main shaft 14 has associated therewith an auxiliary shaft 20 which extends parallel to the main shaft 14 in the cavity 13 but which, being shorter than the main shaft, is entirely contained in the cavity 13.

The auxiliary shaft 20 is mounted for rotation in bearings 21 secured to the cylinder 10, and is disposed nearer the periphery of the cylinder than is the main shaft 14. The auxiliary shaft 20 is situated down-stream of the main shaft 14, considered in the direction of rotation of the cylinder 10, which direction is indicated by arrow 22 in FIG. 5.

The auxiliary shaft 20 is driven by the main shaft 14 by means of a transmission linkage 23, which in the example illustrated, and can be seen more clearly in FIG. 4, comprises a first lever 24 rockable on the main shaft 14, a second lever 25 rockable on the auxiliary shaft 20, and a connecting rod 26 articulated at 27 to the first lever 24 and at 28 to the second lever 25.

The second lever 25 preferably has a length L2, FIG. 4, shorter than the length Ll of the first lever 24.

Two identical stops 30 are spaced apart axially along and are secured to the auxiliary shaft 20.

One of the stops 30 is illustrated in FIG. 3 and comprises a stop lever 31 fastened on the auxiliary shaft 20 and a stop heel 32, the position of which is preferably adjustable on the lever 31 and which in the position of rest, as illustrated in FIG. 3, projects slightly beyond the periphery of the cylinder 10 in the proximity of the rear edge 33 of the cavity 13. The position of rest is defined by an auxiliary stop 34.

Each of the stops 30 has associated therewith two identical grippers 35, FIGS. 1, 2 and 5, disposed one on each side of the stop. As shown in FIG. 2, a gripper comprises a gripper lever 36 secured to the auxiliary shaft 20, and a gripper member 37 which, in the position of rest as illustrated, is engaged over a support plate 38 attached to the cylinder 10 level with the periphery of the cylinder. The gripper member 37 is pivotally mounted on the gripper lever 36 by means of a pivot 50 and is constantly biased towards the cylinder 10 and the support plate 38 by a spring 51 reacting against the gripper lever 36 and the gripper member 37. Pivoting of the gripper member 37 towards the cylinder 10 is limited by a stop portion 52 positioned in a notch 53 in the gripper lever 36 for limited movement.

The sheet feeding cylinder 10 is usually associated with an applicator cylinder 40, which is illustrated only partially and diagrammatically in broken lines in FIGS. 5 and 6.

The axes of the cylinders 10 and 40 are parallel and at a distance slightly greater than the sum of the radii of the cylinders.

A sheet 41 to be treated is pushed by a push-rod 42 in a feed plane 43, FIG. 5, for the purpose of introduction between the cylinders 10 and 40.

During movement of the sheet 41 by the push-rod 42 the sheet is guided transversely, that is to say perpendicularly to the axis of the cylinders 10 and 40, by lateral guides, not shown.

The profile of the cam 18 is such that for a first position illustrated in FIG. 5, the stops 30 of the cylinder 10 project considerably beyond the cavity 13 of the cylinder and are thus interposed in the path of the sheet 41, at a distance from the plane P containing the axis of the cylinders, as diagrammatically illustrated in FIG. 5.

The thus increased projection of the stops 30 is due to the relatively great length of the stop levers 31, which is made possible by the fact that the auxiliary shaft 20 is closer to the periphery of the cylinder 10, and is disposed downstream of the main shaft 14.

The increased projection of the stops 30 is further due to the step-down ratio introduced between the rocking movements of the shafts l4 and 20 due to the fact that in the transmission linkage connecting the shafts the lever 25 secured to the auxiliary shaft 20 is shorter than the lever 24 secured to the main shaft 14.

In the position P1 illustrated in FIG. 5 the leading edge of the sheet 41 pushed by the push-rods 42 comes into contact with the stops 30.

The push-rods 42 maintain their action and continue to urge the sheet 41 towards the stops 30, so that any rebounding and/or vibration of the sheet is definitely damped before the effective operation of the applicator cylinder 40, provided that the positioning time between the first contact of the sheet 41 with the stops 30 and the commencement of the effective work is sufficient.

In practice the end of the positioning time is determined by the gripping of the leading edge portion of the sheet 41 by the grippers 35 associated with the stops 30.

This gripping is effected in the position P2 illustrated in FIG. 6, slightly beyond the plane P containing the axes of the cylinders and 40.

Because of the increased projection of the stops 30 as described above the time allowed for positioning the sheet 41 is particularly long, and the angular path separating the two positions P1, P2 of the feed cylinder may attain 45, whereas in previous feed cylinders it scarcely attains25.

What I claim is:

1. In combination with a sheet feeding cylinder for feeding sheets and wherein said cylinder has an axis, peripheral drive means on at least one end of said cylinder for rotating said cylinder about said axis and a lon gitudinal cavity therein parallel to said axis; a first shaft, said first shaft being a main shaft, means mounting said first shaft in said cavity, control means disposed beyond said cylinder connected to said first shaft for driving said first shaft, a second shaft, said second shaft being an auxiliary shaft and having ends terminating within said cavity, at least one stop lever on said second shaft cooperable with a leading edge of each sheet being fed to said cylinder, means mounting said second shaft in said cavity parallel to said first shaft and for rotation with said second shaft being disposed substantially outwardly beyond said first shaft relative to said cylinder axis for reducing the deceleration of a sheet engaging said stop lever and providing a more gradual reaceleration of the sheet following the deceleration thereby assuring the stabilization of the sheet as it is engaged with said cylinder, and transmission means connecting together said shafts for rotation relative to one another.

2. A sheet feeding cylinder according to claim 1, wherein the transmission linkage comprises a first lever secured to said first-mentioned shaft, a second lever secured to the auxiliary shaft, and a connecting rod pivotally connected to the levers.

3. A sheet feeding cylinder according to claim 2, wherein the length of the second lever is less than that of the first lever.

4. A sheet feeding cylinder according to claim 1, wherein the auxiliary shaft is disposed downstream of said first-mentioned shaft considered in the direction of rotation of the cylinder.

5. In combination with a sheet feeding cylinder for feeding sheets and wherein said cylinder has an axis and a longitudinal cavity therein parallel to said axis, a shaft disposed within said cavity, means mounting said shaft for rotation and drive means disposed beyond said cylinder connected to said shaft for effecting rotation of said shaft, at least one stop lever fixedly carried by said shaft for rotation therewith and for cooperating in abutting relation with a leading edge of a sheet delivered to said cylinder, an auxiliary stop carried by said cylinder within said cavity for engagement by said stop lever to limit rotation of said shaft and said stop lever, at least one gripper lever carried by said shaft for rotation therewith, a gripper, means pivotally mounting said gripper on said gripper lever, and spring means biasing said gripper towards said cylinder for gripping an edge of a sheet against said cylinder.

6. A sheet feeding cylinder in accordance with claim 5 together with a second shaft disposed in said cavity and connected to said drive means, and transmission linkage between the first-mentioned shaft and said second shaft for driving said first-mentioned shaft by said drive means.

7. A sheet feeding cylinder according to claim 6, wherein the first-mentioned shaft is wholly contained in the cavity in the cylinder.

8. A sheet feeding cylinder according to claim 6, wherein the transmission linkage comprises a first lever secured to said second shaft, a second lever secured to said first-mentioned shaft, and a connecting rod pivotally connected to said levers.

9. A sheet feeding cylinder according to claim 8, wherein the length of the second lever is less than that of the first lever.

10. A sheet feeding cylinder according to claim 6, wherein said first-mentioned shaft is disposed downstream of said second shaft considered in the direction of rotation of the cylinder.

UNITED STATES PATENT OFFICEE CERTIFICATE OF CORRECTION Patent No. 3 78 8 639 Dated January 29 1974 Inventoflg) MIICI-IETI BRU It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On the information page, item 73, the name of the assignee should be changed to correctly read as follows:

ETS J. J. CARNAUD & FORGES DE BASSE-INDRE Signed andsealed this 16th day of July 1974.

(SEAL) I Attest:

MCCOY M.' GIBSON, JR. 1 c. MARSHALL DANN Attesting Officer a Commissioner of Patents FORM po'mso I I USCOMM-DC 60376-P69 0.5. GOVERNMENT PRINTING OFFICE II. O-QGG-SSJV 

1. In combination with a sheet feeding cylinder for feeding sheets and wherein said cylinder has an axis, peripheral drive means on at least one end of said cylinder for rotating said cylinder about said axis and a longitudinal cavity therein parallel to said axis; a first shaft, said first shaft being a main shaft, means mounting said first shaft in said cavity, control means disposed beyond said cylinder connected to said first shaft for driving said first shaft, a second shaft, said second shaft being an auxiliary shaft and having ends terminating within said cavity, at least one stop lever on said secoNd shaft cooperable with a leading edge of each sheet being fed to said cylinder, means mounting said second shaft in said cavity parallel to said first shaft and for rotation with said second shaft being disposed substantially outwardly beyond said first shaft relative to said cylinder axis for reducing the deceleration of a sheet engaging said stop lever and providing a more gradual re-aceleration of the sheet following the deceleration thereby assuring the stabilization of the sheet as it is engaged with said cylinder, and transmission means connecting together said shafts for rotation relative to one another.
 2. A sheet feeding cylinder according to claim 1, wherein the transmission linkage comprises a first lever secured to said first-mentioned shaft, a second lever secured to the auxiliary shaft, and a connecting rod pivotally connected to the levers.
 3. A sheet feeding cylinder according to claim 2, wherein the length of the second lever is less than that of the first lever.
 4. A sheet feeding cylinder according to claim 1, wherein the auxiliary shaft is disposed downstream of said first-mentioned shaft considered in the direction of rotation of the cylinder.
 5. In combination with a sheet feeding cylinder for feeding sheets and wherein said cylinder has an axis and a longitudinal cavity therein parallel to said axis, a shaft disposed within said cavity, means mounting said shaft for rotation and drive means disposed beyond said cylinder connected to said shaft for effecting rotation of said shaft, at least one stop lever fixedly carried by said shaft for rotation therewith and for cooperating in abutting relation with a leading edge of a sheet delivered to said cylinder, an auxiliary stop carried by said cylinder within said cavity for engagement by said stop lever to limit rotation of said shaft and said stop lever, at least one gripper lever carried by said shaft for rotation therewith, a gripper, means pivotally mounting said gripper on said gripper lever, and spring means biasing said gripper towards said cylinder for gripping an edge of a sheet against said cylinder.
 6. A sheet feeding cylinder in accordance with claim 5 together with a second shaft disposed in said cavity and connected to said drive means, and transmission linkage between the first-mentioned shaft and said second shaft for driving said first-mentioned shaft by said drive means.
 7. A sheet feeding cylinder according to claim 6, wherein the first-mentioned shaft is wholly contained in the cavity in the cylinder.
 8. A sheet feeding cylinder according to claim 6, wherein the transmission linkage comprises a first lever secured to said second shaft, a second lever secured to said first-mentioned shaft, and a connecting rod pivotally connected to said levers.
 9. A sheet feeding cylinder according to claim 8, wherein the length of the second lever is less than that of the first lever.
 10. A sheet feeding cylinder according to claim 6, wherein said first-mentioned shaft is disposed downstream of said second shaft considered in the direction of rotation of the cylinder. 